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Commentary on "Association of daily sitting time and leisure-time physical activity with body fat among U.S.adults"
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作者 Barbara E.Ainsworth 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第2期127-129,共3页
In their study,association of daily sitting time and leisure-time physical activity (LTPA) with body fat among U.S.Adults,Liao et al.^(1) analyzed data from the 2011-2018 National Health and Examination Survey to exam... In their study,association of daily sitting time and leisure-time physical activity (LTPA) with body fat among U.S.Adults,Liao et al.^(1) analyzed data from the 2011-2018 National Health and Examination Survey to examine associations between h/day sitting,meeting (or not meeting) the U.S.Physical Activity Guidelines of≥150 min/week of moderate-and vigorous-intensity LTPA,and combinations of sitting time and LTPA on totaland trunk percent body fat (BF%). 展开更多
关键词 u.s. ADULT AMONG
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The Reception Commemorating the 45th Anniversary of China-U.S.Diplomatic Ties Held in Beijing
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《International Understanding》 2024年第1期40-40,共1页
On January 5,the Chinese People's Association for Friendship with Foreign Countries and the Chinese People's Institute of Foreign Affairs jointly hosted a reception commemorating the 45th anniversary of the es... On January 5,the Chinese People's Association for Friendship with Foreign Countries and the Chinese People's Institute of Foreign Affairs jointly hosted a reception commemorating the 45th anniversary of the establishment of diplomatic relationship between China and the United States in Beijing.Member of the Political Bureau of the CPC Central Committee and Foreign Minister Wang Yi attended the commemoration and delivered aspeech.David Meale,ChargédAffaires at the U.S.Embassy in China,addressed the reception.He extended on behalf of the U.S.side congratulations on the anniversary,expressing the readiness of the U.S.to implement the consensus reached by the two heads of state and promote the steady development of U.S.-China relations.More than 350 people from all walks of life of both countries attended the reception. 展开更多
关键词 jointly u.s. behalf
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FREE SPEECH OR SINOPHOBIA? THE U.S. SENATE MUST DECIDE
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作者 Anthony Moretti 《China Report ASEAN》 2024年第4期63-64,共2页
The 100 men and women who make up the U.S.Senate will soon have an important choice.They will either affirm that the First Amendment matters or they will surrender to fear.The senators must decide whether to go along ... The 100 men and women who make up the U.S.Senate will soon have an important choice.They will either affirm that the First Amendment matters or they will surrender to fear.The senators must decide whether to go along with their colleagues in the House of Representatives and require the popular social media app TikTok to be sold to an American company.If they do endorse the House vote,then ByteDance must divest itself of TikTok or see the app will be banned on U.S.-based social media platforms. 展开更多
关键词 u.s. RENDER SOON
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Cross-Cultural Adjustment and Coping:U.S.Students in Taiwan Residents Higher Education
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作者 Wen-Ling Lou 《Sino-US English Teaching》 2024年第1期26-42,共17页
The aim of this study was to investigate the adjustment problems of students from the United States enrolled in universities in the East,specifically in Taiwan,their problems related to cultural adaptation,and the pro... The aim of this study was to investigate the adjustment problems of students from the United States enrolled in universities in the East,specifically in Taiwan,their problems related to cultural adaptation,and the process of adjustment to student life in Taiwan.Under investigation were cultural adjustment and coping skills as these students transitioned from West to East.Qualitative data were collected from interviews with participants and faculty members as well as participant observations.Results indicated that U.S.students found their own ways to acclimate to their new academic setting as well as to social relations,cross-cultural issues,and the linguistic environment in Taiwan to achieve effective adaptation.They made changes in themselves to cope with all situations they encountered.This study provides suggestions for international students abroad in Taiwan,for the Taiwan Residents government,and for universities or colleges in terms of what they should offer to current and future international students. 展开更多
关键词 adjustment cultural adjustment cross-cultural adaptation COPING u.s.students
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The Influence of Christian Nationalism on U.S.Foreign Policy
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作者 PU Jingxin 《International Relations and Diplomacy》 2024年第5期191-195,共5页
This paper explores the influence of Christian nationalism on U.S.foreign policy,examining its historical roots,ideological foundations,and contemporary implications.Christian nationalism,an ideology that links Christ... This paper explores the influence of Christian nationalism on U.S.foreign policy,examining its historical roots,ideological foundations,and contemporary implications.Christian nationalism,an ideology that links Christianity with national identity,has shaped U.S.foreign policy in areas such as religious freedom,Middle East diplomacy,and national security.Through its emphasis on the moral duty to defend Christianity and its promotion of conservative social values,Christian nationalism has affected U.S.relations with countries around the world,particularly in the Middle East and with religious minorities.The paper discusses the complexities and controversies surrounding Christian nationalism,its impact on the U.S.’s global image,and the challenges it poses to religious pluralism.The future of Christian nationalism’s influence on U.S.foreign policy is uncertain,as societal shifts and evolving global dynamics may prompt a reevaluation of its role in shaping America’s international actions.Overall,the paper provides a nuanced analysis of how Christian nationalism has intertwined with U.S.foreign policy and how its influence might evolve in the future. 展开更多
关键词 Christian nationalism u.s.foreign policy religious freedom Middle East diplomacy American exceptionalism
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Digital Disparities:How Artificial Intelligence Can Facilitate Anti-Black Racism in the U.S.Healthcare Sector
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作者 Anthony Victor Onwuegbuzia 《International Relations and Diplomacy》 2024年第1期40-50,共11页
This paper delves into the intricate interplay between artificial intelligence(AI)systems and the perpetuation of Anti-Black racism within the United States medical industry.Despite the promising potential of AI to en... This paper delves into the intricate interplay between artificial intelligence(AI)systems and the perpetuation of Anti-Black racism within the United States medical industry.Despite the promising potential of AI to enhance healthcare outcomes and reduce disparities,there is a growing concern that these technologies may inadvertently/advertently exacerbate existing racial inequalities.Focusing specifically on the experiences of Black patients,this research investigates how the following AI components:medical algorithms,machine learning,and natural learning processes are contributing to the unequal distribution of medical resources,diagnosis,and health care treatment of those classified as Black.Furthermore,this review employs a multidisciplinary approach,combining insights from computer science,medical ethics,and social justice theory to analyze the mechanisms through which AI systems may encode and reinforce racial biases.By dissecting the three primary components of AI,this paper aims to present a clear understanding of how these technologies work,how they intersect,and how they may inherently perpetuate harmful stereotypes resulting in negligent outcomes for Black patients.Furthermore,this paper explores the ethical implications of deploying AI in healthcare settings and calls for increased transparency,accountability,and diversity in the development and implementation of these technologies.Finally,it is important that I prefer the following paper with a clear and concise definition of what I refer to as Anti-Black racism throughout the text.Therefore,I assert the following:Anti-Black racism refers to prejudice,discrimination,or antagonism directed against individuals or communities of African descent based on their race.It involves the belief in the inherent superiority of one race over another and the systemic and institutional practices that perpetuate inequality and disadvantage for Black people.Furthermore,I proclaim that this form of racism can be manifested in various ways,such as unequal access to opportunities,resources,education,employment,and fair treatment within social,economic,and political systems.It is also pertinent to acknowledge that Anti-Black racism is deeply rooted in historical and societal structures throughout the U.S.borders and beyond,leading to systemic disadvantages and disparities that impact the well-being and life chances of Black individuals and communities.Addressing Anti-Black racism involves recognizing and challenging both individual attitudes and systemic structures that contribute to discrimination and inequality.Efforts to combat Anti-Black racism include promoting awareness,education,advocacy for policy changes,and fostering a culture of inclusivity and equality. 展开更多
关键词 Bias in algorithms Racial disparities in u.s.healthcare Discriminatory healthcare practices Black patient outcomes Automated decision-making and racism Machine Learning Natural language processing
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普通铅对LA-ICP-MS磷灰石U-Pb定年结果的影响及校正方法
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作者 罗涛 王瀚林 +2 位作者 朱松柏 卿丽媛 胡兆初 《岩矿测试》 CAS 北大核心 2025年第1期51-62,共12页
磷灰石是火成岩、变质岩和沉积岩中广泛分布的含铀矿物,开展磷灰石U-Pb年代学研究对揭示岩浆演化过程、示踪溯源等方面具有重要意义。激光剥蚀电感耦合等离子体质谱法(LA-ICP-MS)是开展磷灰石U-Pb年龄微区分析的重要手段之一。当前,基... 磷灰石是火成岩、变质岩和沉积岩中广泛分布的含铀矿物,开展磷灰石U-Pb年代学研究对揭示岩浆演化过程、示踪溯源等方面具有重要意义。激光剥蚀电感耦合等离子体质谱法(LA-ICP-MS)是开展磷灰石U-Pb年龄微区分析的重要手段之一。当前,基体匹配磷灰石U-Pb定年矿物标样缺乏和标样中不可避免的普通铅是制约LA-ICP-MS高精度磷灰石U-Pb年龄分析的主要瓶颈。本文对比研究了标样中普通铅对LA-ICP-MS磷灰石U-Pb定年结果的影响,采用含普通铅的磷灰石MAD作外标直接开展U-Pb年龄校正,获得的被测样品年龄会产生显著的系统偏差(最大约6%);采用207Pb法或Tera-Wasserburg图解法先校正标样中普通铅,再利用校正后的数据进行元素分馏和仪器漂移校正则可获得准确的磷灰石U-Pb年龄,与推荐值偏差在2%以内。另一方面,为消除标样中普通铅对分析结果的影响,本文还采用水蒸气辅助激光剥蚀方法,实现以NIST612玻璃作为外标准确分析磷灰石U-Pb年龄,解决了磷灰石U-Pb定年微区分析高质量标样缺乏的难题。本研究通过对标样中普通铅进行预校正或采用非基体匹配分析,建立了高精度LA-ICP-MS磷灰石U-Pb定年新方法,将促进磷灰石U-Pb年代学在地球科学研究中的应用。 展开更多
关键词 激光剥蚀电感耦合等离子体质谱法 磷灰石 U-PB定年 普通铅校正 非基体匹配分析
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中国主要类型铅锌矿床S、Pb、C-H-O同位素特征及其成因意义
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作者 刘榆 江彪 +4 位作者 王登红 王岩 宋学信 张长青 黄凡 《地球学报》 北大核心 2025年第1期93-115,共23页
铅、锌是重要的矿产资源,在工业生产中发挥着至关重要的作用。S、Pb、C-H-O同位素地球化学可以用来解释成矿物质来源、成矿流体来源及矿床成因等地质问题。对铅锌矿床的稳定同位素研究自20世纪80年代至今已取得丰硕成果,为从单矿种角度... 铅、锌是重要的矿产资源,在工业生产中发挥着至关重要的作用。S、Pb、C-H-O同位素地球化学可以用来解释成矿物质来源、成矿流体来源及矿床成因等地质问题。对铅锌矿床的稳定同位素研究自20世纪80年代至今已取得丰硕成果,为从单矿种角度进行全国性的总结奠定了良好基础。本文基于全国重要铅锌矿床的相关硫、铅、氢、氧、碳同位素近万条数据进行分析,结果显示,中国铅锌矿床的S、Pb同位素特征揭示其成矿物质来源复杂,主要为深源岩浆和赋矿地层(海水沉积物),H-O、C-O同位素特征表明中国铅锌矿床的成矿流体中的水主要为岩浆水和大气降水,而成矿流体中的碳主要来源于岩浆和海相碳酸盐岩。S同位素的空间分布特征显示,从我国西部到东部地区,北部到南部地区,铅锌矿床的32S趋于富集,表明我国东部和南部铅锌矿床有更多壳源物质参与成矿。C-H-O同位素特征显示相较于西北部地区,我国东南部地区的铅锌矿床有更多大气降水或盆地卤水参与成矿。 展开更多
关键词 铅锌矿 S同位素 PB同位素 C-H-O同位素 地球化学
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芳纶铺层-蜂窝夹芯U形前缘固化变形仿真计算模型与验证
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作者 刘琦 唐珊珊 +3 位作者 王小凯 郭俊刚 牛建文 许英杰 《复合材料科学与工程》 北大核心 2025年第1期51-58,共8页
本文采用有限元仿真和试验验证相结合的方法,对芳纶纤维-蜂窝夹芯U形前缘结构的固化变形问题进行了研究。在仿真建模中,充分考虑了树脂的固化放热、热-力耦合以及化学收缩等,建立了U形前缘的固化温度场和固化变形场计算模型。在试验制备... 本文采用有限元仿真和试验验证相结合的方法,对芳纶纤维-蜂窝夹芯U形前缘结构的固化变形问题进行了研究。在仿真建模中,充分考虑了树脂的固化放热、热-力耦合以及化学收缩等,建立了U形前缘的固化温度场和固化变形场计算模型。在试验制备中,采用了预先固化外蒙皮,再与蜂窝芯、胶膜、发泡胶组合,最后铺放内蒙皮并再次胶接固化的成型工艺。结果显示,仿真模型预测的构件宽侧与窄侧的固化变形量与实际吻合度较高,可为后续前缘构件的模具修型提供指导和依据。 展开更多
关键词 固化成型 芳纶复合材料 蜂窝夹芯 U形前缘 有限元计算
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RTAs纺织品协定对中国的影响及对策研究——以U.S.-DR-CAFTA纺织品协定为例 被引量:1
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作者 查志强 《世界经济研究》 CSSCI 北大核心 2006年第5期17-21,10,共6页
RTAs纺织品协定将对中国纺织品国际贸易产生较大影响。本文以U.S.-DR-CAFTA纺织品协定为例,对其内容进行了阐述,认为该协定是美国在全球纺织品贸易“后配额时代”打压中国纺织业的一项重要手段。中国纺织企业应充分解读该协定的相关条款... RTAs纺织品协定将对中国纺织品国际贸易产生较大影响。本文以U.S.-DR-CAFTA纺织品协定为例,对其内容进行了阐述,认为该协定是美国在全球纺织品贸易“后配额时代”打压中国纺织业的一项重要手段。中国纺织企业应充分解读该协定的相关条款,趋利避害,从而避免贸易壁垒的限制,加快融入全球化的步伐。 展开更多
关键词 区域贸易协定 纺织品协定 u.s.-DR-CAFTA
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“Speech on Hitler’s Invasion of the U.S.S.R.”(汉译文)的美学赏析
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作者 高扩昌 任桂婷 《美与时代(美学)(下)》 2008年第5期122-125,共4页
语言作为人类精神的产物和文明的载体应具有审美价值,而演讲作为一种特殊的语言表现形式,它的审美价值在于能够使受众在愉悦中自觉地去接受或容纳演讲的主旨。Speech on Hitler’s Invasion of the U.S.S.R.是丘吉尔政治生涯中重要的演... 语言作为人类精神的产物和文明的载体应具有审美价值,而演讲作为一种特殊的语言表现形式,它的审美价值在于能够使受众在愉悦中自觉地去接受或容纳演讲的主旨。Speech on Hitler’s Invasion of the U.S.S.R.是丘吉尔政治生涯中重要的演讲作品之一,既具有时效性和实效性,又具有历久弥新的语言审美价值。 展开更多
关键词 演讲者 政治生涯 语言美学 s Invasion of the u.s.S.R Speech on Hitler 丘吉尔 意义潜势
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从《漂亮的三丫头》与“Miss U.S.A.”原、译文的交叉比较看口述实录文学的特点
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作者 魏芳 《北京印刷学院学报》 2011年第3期50-53,共4页
口述实录文学作品主要通过口语形式表达,属于谈话语体,其特点是句子结构简洁,语言通俗流畅、形象生动,有强烈的生活气息。《漂亮的三丫头》和"Miss U.S.A."是题材风格非常接近,极有可比性的两篇口述实录文学作品。通过对《漂... 口述实录文学作品主要通过口语形式表达,属于谈话语体,其特点是句子结构简洁,语言通俗流畅、形象生动,有强烈的生活气息。《漂亮的三丫头》和"Miss U.S.A."是题材风格非常接近,极有可比性的两篇口述实录文学作品。通过对《漂亮的三丫头》与"Miss U.S.A."的原、译文作交叉对照评析,能很好地检验各自译文在语体风格上对原文的忠实程度。 展开更多
关键词 MISS u.s.A 漂亮的三丫头 翻译 语体风格
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新质生产力视域下的U-G-S模式智慧校园建设
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作者 林德力 《福建电脑》 2025年第1期41-49,共9页
智慧教育是教育体系建设中非常重要的一环,培养合格的新质生产力的劳动者是智慧校园建设的目标之一。本文研究和分析新质生产力、U-G-S模式与智慧校园建设之间的关联性,并以实例展示基于新质生产力的U-G-S模式智慧校园总体架构模型。对... 智慧教育是教育体系建设中非常重要的一环,培养合格的新质生产力的劳动者是智慧校园建设的目标之一。本文研究和分析新质生产力、U-G-S模式与智慧校园建设之间的关联性,并以实例展示基于新质生产力的U-G-S模式智慧校园总体架构模型。对该模型的实施效果调查分析的结果表明,U-G-S模式下的智慧校园运行获得了较为满意的效果。 展开更多
关键词 U-G-S模式 智慧校园 新质生产力
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the U.S. Poet Laureate与the Poet Laureate有何不同
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作者 王勇 《英语知识》 2004年第2期46-46,共1页
[问][419]请问the U.S.Poet Laureate与thePoet Laureate有何不同?[答]《牛津现代高级英汉双解词典》(商务印书馆&牛津大学出版社2001年版)对the PoetLaureate的解释为“桂冠诗人”(英国国王所任命者,视为王室之一员,获此荣誉者于... [问][419]请问the U.S.Poet Laureate与thePoet Laureate有何不同?[答]《牛津现代高级英汉双解词典》(商务印书馆&牛津大学出版社2001年版)对the PoetLaureate的解释为“桂冠诗人”(英国国王所任命者,视为王室之一员,获此荣誉者于国家大典时可能写诗庆祝)。因此我们可以称之为“ 展开更多
关键词 “the u.s. POET Laureate” “the POET Laureate” 区别 英语 翻译
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Comparison of Corn Production Costs in China,the U.S. and Brazil and Its Implications 被引量:3
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作者 钱福凤 杨军 Danielle Alencar ParenteTorres 《Agricultural Science & Technology》 CAS 2016年第3期731-736,共6页
This paper analyzes the corn production cost in China, the U.S. and Brazil from 1997 to 2014. According to the results,(1) corn production cost in China is the highest among these three countries;(2) the rapid gro... This paper analyzes the corn production cost in China, the U.S. and Brazil from 1997 to 2014. According to the results,(1) corn production cost in China is the highest among these three countries;(2) the rapid growth of labor cost and land cost is the major factor that promotes the increase of total corn production cost in China;(3) the level of agricultural mechanization in China has been gradually improving, and the gap between agricultural mechanization levels in China and other two countries is constantly narrowing;(4) differing from the U.S. and Brazil,China exhibits a "high input, low output" agricultural production mode. Based on the above analyses, corresponding suggestions have been presented to reduce corn production cost in China. 展开更多
关键词 CORN Production cost China the u.s Brazil
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基于U.S. News排名的美国档案学研究生教育特点及启示——兼论信息科学视野下的档案学研究生培养 被引量:1
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作者 李佩蓉 崔旭 李姗姗 《档案与建设》 北大核心 2019年第4期40-44,8,共6页
论文选取2017年在美国U.S.News排名前十的档案学院校,从培养理念目标、课程设置、师资队伍建设及专业实践四个方面进行了分析。信息科学视野下的美国档案学研究生教育采用"信息科学大背景+档案学专门化"的教育模式,具备创新... 论文选取2017年在美国U.S.News排名前十的档案学院校,从培养理念目标、课程设置、师资队伍建设及专业实践四个方面进行了分析。信息科学视野下的美国档案学研究生教育采用"信息科学大背景+档案学专门化"的教育模式,具备创新精神和奉献社会的研究生人才培养观,以及紧密结合信息社会需求的研究生职业素养观。借鉴美国档案学研究生教育经验,我国档案学研究生教育应兼顾信息科学与档案学核心内容,优化课程体系;构建多元化的师资队伍,增进跨学科教师合作;注重开展专业实习和社会实践活动,帮助研究生树立职业规划理念;注重思想道德教育,培养档案学研究生的奉献精神和社会服务价值观。 展开更多
关键词 u.s.News排名 美国高校 档案学 信息科学 研究生教育
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China’s alfalfa market and imports: Development, trends, and potential impacts of the U.S.-China trade dispute and retaliations 被引量:4
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作者 Qingbin WANG ZOU Yang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第4期1149-1158,共10页
This study examines the development and trends of China’s alfalfa market and imports, identifies key factors for the rapid increase in China’s alfalfa imports, and discusses potential impacts of the U.S.-China trade... This study examines the development and trends of China’s alfalfa market and imports, identifies key factors for the rapid increase in China’s alfalfa imports, and discusses potential impacts of the U.S.-China trade dispute and retaliations on the alfalfa markets and trade in both nations. China’s rapid transition toward larger-scale commercial dairy production, with enhanced feed and cost management as well as quality and safety control, and its limited resources for high-quality alfalfa production are key factors for the dramatic increase in its alfalfa imports, from 19 601 metric tons in 2008 to 1.38 million metric tons(mmt) in 2018. While the United States dominated China’s alfalfa imports with an average share of 97.01% from 2007 to 2017, the share dropped to 83.76% in 2018 and 63.28% in January 2019 due to the trade dispute and retaliations started in 2018. China will likely remain a large importer of alfalfa because of both its growing demand and the comparative advantages of imported alfalfa in quality and price, but the imports from the United States will be highly affected by the ongoing trade dispute and negotiations. China is also expected to make more efforts to reduce its dependence on U.S. alfalfa through increased investment in domestic alfalfa production and identification of alternative sources of alfalfa and other hay imports. 展开更多
关键词 China’s ALFALFA IMPORTS u.s.alfalfa EXPORTS dairy industrialization u.s.-China trade DISPUTE and retaliations GM-free standards
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The withdrawal of the U.S. from the Paris Agreement and its impact on global climate change governance 被引量:5
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作者 ZHANG Yong-Xiang CHAO Qing-Chen +1 位作者 ZHENG Qiu-Hong HUANG Lei 《Advances in Climate Change Research》 SCIE CSCD 2017年第4期213-219,共7页
The global community has prepared for the withdrawal of the U.S. from the Paris Agreement since Donald Trump was elected as the president of the U.S. However, Trump's formal declaration of withdrawal still caused ... The global community has prepared for the withdrawal of the U.S. from the Paris Agreement since Donald Trump was elected as the president of the U.S. However, Trump's formal declaration of withdrawal still caused worldwide reaction. Trump will use the withdrawal to build his political reputation and to renegotiate the Paris Agreement despite its negative effects on the political credibility, international relationships, and potential long-term economic growth of the U.S. In general, the withdrawal of the U.S. from the Paris Agreement will not change the development of low-carbon technologies and the transformation trend of the global climate governance regime. However, the long-term goals and international cooperation on climate change will be affected by budget cuts in American climate change research and the cancelation of donations from the multilateral environmental fund of the U.S. If the Paris Agreement is renegotiated, the common but differentiated principle of responsibility of the United Nations Framework Convention on Climate Change will be challenged again. Nevertheless, climate change governance remains a main theme of future sustainable development. Instead of national governments, local governments and non-governmental organizations will develop strategies for technical innovation and emphasize pragmatic cooperation, thus expanding their roles in climate change governance. The capacity building on climate change research and public awareness should be enhanced as a long-term objective of global climate change governance. 展开更多
关键词 u.s. withdraw PARIS AGREEMENT Global climate change GOVERNANCE IMPACT
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Investigation of factors influencing roof stability at a Western U.S.longwall coal mine 被引量:3
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作者 Meriel Young Gabriel Walton Elizabeth Holley 《International Journal of Mining Science and Technology》 EI CSCD 2019年第1期139-143,共5页
The coal mine roof rating(CMRR) was developed to bridge the gap between geological variation in underground coal mines and engineering design. The CMRR accounts for the compressive strength of the immediate roof, the ... The coal mine roof rating(CMRR) was developed to bridge the gap between geological variation in underground coal mines and engineering design. The CMRR accounts for the compressive strength of the immediate roof, the shear strength and intensity of any discontinuities present, and the moisture sensitivity of the immediate roof. The CMRR has been widely used and validated in Eastern US coal mines, but it has seen limited application in the Western US. This study focuses on roof behavior at a Western coal mine(Mine A). Mine A shows significant lateral geological variation, along with localized faulting and a laterally extensive sandstone channel network. The CMRR is not used to predict roof instability at the mine. It is, therefore, hypothesized that there are other factors that are correlated with roof instability in underground coal mines that could potentially also be considered in conjunction with the CMRR.This hypothesis was tested by collecting 30 CMRR measurements at Mine A. At each measurement location, a binary record of the roof condition(stable or unstable) was made, and other parameters such as depth of cover, presence of faulting, and sandstone channels were also recorded. ANOVA tests showed that the CMRR values and the roof conditions were not strongly correlated, indicating that the CMRR input criteria are not fully predictive of roof stability at this mine. The CMRR values showed statistically significant correlations(p less than 0.05) with faulting as well as with location at an intersection. For areas that had previously experienced roof fall but were currently stable, faulting was correlated with roof condition(p less than 0.05) only when the condition was classified as unstable. 展开更多
关键词 COAL MINE ROOF stability CMRR WESTERN u.s.coal Case study
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PHOTOREALISTIC COMPUTER GRAPHICS FORENSICS BASED ON LEADING DIGIT LAW 被引量:3
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作者 Xu Bo Wang Junwen Liu Guangjie Dai Yuewei 《Journal of Electronics(China)》 2011年第1期95-100,共6页
As the advent and growing popularity of image rendering software,photorealistic computer graphics are becoming more and more perceptually indistinguishable from photographic images.If the faked images are abused,it ma... As the advent and growing popularity of image rendering software,photorealistic computer graphics are becoming more and more perceptually indistinguishable from photographic images.If the faked images are abused,it may lead to potential social,legal or private consequences.To this end,it is very necessary and also challenging to find effective methods to differentiate between them.In this paper,a novel leading digit law,also called Benford's law,based method to identify computer graphics is proposed.More specifically,statistics of the most significant digits are extracted from image's Discrete Cosine Transform(DCT) coefficients and magnitudes of image's gradient,and then the Support Vector Machine(SVM) based classifiers are built.Results of experiments on the image datasets indicate that the proposed method is comparable to prior works.Besides,it possesses low dimensional features and low computational complexity. 展开更多
关键词 leading digit law Benford’s law Digital image forensic Computer graphics
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